<%= table_for @npw do |t|
  t.column :id 
  t.column :first_name 
  t.column :last_name 
  t.column :category 
  t.column :year 

  t.filter :category,
    collection: ['Chemistry', 'Literature', 'Peace', 'Physics', 'Physiology or Medicine'],
    multiple:   true
end %>
